I think it's because of how the extra content stuff was apparently online based, so wouldn't work without the Presence Labs server. Or perhaps Presence Labs had it pulled when they shut down.Zynga had Mountain Goat Mountain removed from the Oculus store, but people who own it (like me) can still download and play it, it's just not available to new people (which is a shame, it's a great little game). It didn't need any online parts to run, so it was safe to leave available to existing owners.
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